Clinical Evaluation of Viscum album Homeopathic Mother Tincture as an Antihypertensive

A Pilot Study has been published in the Journal of Evidence Based Complementary and Alternative Medicine which looks at a rarely used homeopathic remedy - and it's use in treating hypertension. Interestingly the medicine that was given to the patients was a preparation of Mistletoe - which has a long history of use throughout Europe, Asia and Africa - and has traditionally been used as a cardiac medication. The researchers found that the Mistletoe extract lowered blood pressure safely and that it also lowered serum triglycerides. The researchers comment that they would like to see Mistletoe extract being used to treat high blood pressure in future, both on it's own and in conjunction with conventional medicines where appropriate.

Here below is the abstract from the article - the full paper can be accessed here

Viscum album, an infrequently used antihypertensive in homeopathy, is evaluated by 1-group pretest–posttest model in primary hypertension. The drug was administered for 12 weeks at a dosage of 10 drops 3 times a day. Using paired t test, a significant drop in blood pressure (P < .0001) and serum triglyceride (P < .0001) was observed in the treatment group. This dual effect of Viscum album shows promise in optimizing therapy for primary hypertension.

Hypertension has a multifactorial etiology that leads to systemic vascular damage that has a propensity to induce cardiovascular as well as noncardiovascular complications. Hypertension follows an insidious onset, at times only noted in routine check-up, which prevents early diagnosis.1 The ever-increasing global morbidity and mortality is pegged down to hypertension. Epidemiological studies have established a strong association between hypertension and fatal and nonfatal events. The long-standing cardiovascular complications of hypertension include atherosclerosis, angina, myocardial infarction, and congestive cardiac failure.2 As hypertension is a chronic illness, drug therapy needs to be taken for a long period (even lifelong). Despite the multitude of antihypertensive drugs available, only 17% to 27% of hypertensives achieve optimal blood pressure.3 The aim of therapy in hypertension is to lower the blood pressure to near-normalcy without incidental fluctuation.

Although the modern system of medicine has a wide array of drugs for treating hypertension, it is confounded by persistently annoying adverse drug reaction. Lowering blood pressure is the main target to reach in the attempt to reduce cardiovascular complications in hypertensive patients.4 Moreover resistant hypertension is not uncommon and is associated with an elevated risk of hypertensive complications. Importantly, the prevalence of multiple disease conditions has been increasing during the past years, suggesting a future increase in the frequency of resistant hypertension.5 In this scenario the search for a novel drug from the alternative system of medicine would be promising and imperative. Homeopathic preparation does offer antihypertensive options of which Viscum album 6 has been used for over 2 centuries.

The crude mistletoe extract prevents changes in erythrocytes, packed cell volume of erythrocytes, plasma protein levels, and erythrocyte sedimentation rate, which indicates that the extract prevents changes in blood viscosity—a major determinant of arterial blood pressure.7 Moreover, an animal trial of Viscum album aqueous extract on albino Wistar rats has shown antihypertensive effect without any change in heart rate.8 Lack of scientific validation by a clinical trial made this drug the choice for this study. Hence, our research initiative is to clinically validate the effect of Viscum album on hypertension by undertaking a simple methodology involving a few laboratory parameters.

The experimental model of “1-group pretest–posttest study” design was taken up due to ethical and administrative reasons. The parameters used in this study to prove the efficacy of the drug are systolic blood pressure, diastolic blood pressure, serum cholesterol, and serum triglycerides. These biochemical parameters were included to find the probable domains of the drug and antecedent beneficial effects. Serum lactate dehydrogenase, serum urea, and serum creatine phosphokinase myocardial band would indicate potential adverse effects.

Viscum album, a bi-perennial shrub distributed widely in tropical and subtropical region of Africa, Asia, and Europe,9 is one of the main medicinal plants used in African folk medicines to treat arterial hypertension.10 The drug showed a significant reduction in the mean value of systolic as well diastolic blood pressure, which could be attributed to a mechanism involving nitric oxide synthase-2 and nitric oxide synthase-3 overexpression and thereby a correlated increase in nitric oxide and cyclic guanosine monophosphate production.11 The aforementioned biochemical process may activate a nonspecific noncompetitive inhibition of calcium (2+) influx as well as Ca (2+) mobilization from intracellular stores.12 The result is vasorelaxation.

The evaluation of biochemical parameters, namely, serum urea, serum lactate dehydrogenase, serum cholesterol, and serum triglycerides, may not give a firm understanding of the pharmacological activity but will definitely give its propensity.

The mean value of serum urea increased from 24.6 to 28.5 mg/dL (P = .01). Although it is a significant increase, none of the individuals of the treatment group had value above normal (normal = 50 mg/dL). This shows that the drug might be safe and may be administered to patients having renal impairment. The above-mentioned observation is further strengthened by the antioxidant studies on liver, kidney, and heart tissues of streptozotocin-induced diabetic rats. This study concludes by stating that Viscum album has a potent antioxidant activity.13 But the study on tolerability of mistletoe among immune-compromised individuals showed an increased serum urea nitrogen and serum creatinine levels.14 Therefore, the observation of a statistically significant increase of serum urea within the normal limits has to be viewed cautiously.

The lipid profile of the treatment group showed statistically significant reduction in triglycerides (P < .0001) and no change in serum cholesterol (P = .142). This observation does not give a clear impression of the antilipidemic property of the drug when viewed in light of research studies conducted by Avci et al15 and Ben et al.16 The study of Avci et al noted reduction in lipid profile of Viscum album–treated mice rats, whereas the study of Ben et al reported increased serum cholesterol in Viscum album–treated male wistar rats. This uncertainty in the antilipidemic property of the drug is further strengthened due to lack of complete lipid profile analysis in the study. This area requires a detailed and a thorough inquiry.

The extract, which is considered to be safe as per preclinical study17 and systematic review of clinical and animal experiments,18 increased levels of serum lactate dehydrogenase and creatine phosphokinase myocardial band in the treatment group. These 2 markers depict the integrity of cardiac muscle. Although the mean value of serum lactate dehydrogenase of the sample rose significantly (P = .006), it was within the normal range, and none of the individuals showed any adverse clinical signs or symptoms. This observation becomes relevant due to the increase of the mean value of creatine phosphokinase myocardial band in which 11 individuals had values above normal limits. The aforementioned parallel rise in cardiac markers gives a strong leaning toward the cardiotoxic capability of the drug, which may be attributed to the presence of viscotoxins19 and lectins20 in the extract.

Hypertension is often associated with dyslipidemia, and therapy with Viscum album will definitely be doubly beneficial for those who are suffering from hypertension and hypertriglyceridemia. This 2-pronged effect of Viscum album would be ideal in treating preeclampsic states where there is hypertension and raised triglycerides.21

Conclusion

Viscum album can be considered as a good choice to regulate blood pressure as well as to lower serum triglyceride levels. The usual pharmacotherapy of hypertension is affected through sympatholytic, vasodilatory, and diuretic effects. The chemical characterization of Viscum album is different from those drugs used in the modern system of medicines and it putatively acts through calcium channels, which could be modulated by other drugs that could lead to synergism. The authors would recommend further comparative clinical studies of Viscum album with other standard pharmacotherapeutic agents.

The increased serum creatine phosphokinase myocardial band level is the only detriment to Viscum album therapy from our study, which has to be validated by toxicology studies on cell lines of cardiac muscles.

We can look forward to promising use of Viscum album therapy per se and in conjunction with drugs of modern system of medicines.